1. Field of the Invention
The present invention relates to an information processing apparatus capable of outputting a plurality of objects according to a drawing order allocated to each object.
2. Description of the Related Art
An application executable by a computer generates various contents including graphics and text objects according to the order of each object in a depth direction (hereinafter, refer to as “drawing order”, “depth position information” or “z-order”). The application can express overlapping of respective objects with reference to the drawing order allocated to each object.
A conventional technique for changing the drawing order of each object generates an instruction such as “shift forward” or “shift rearward” to change an overlapping state of objects. This method can switch a positional relationship between an operation target object and a neighboring object (i.e., an object having a drawing order greater or less by “1” than the operation target object). However, this method has the following problem.
An example illustrated in FIG. 17 includes a plurality of objects 3401 through 3419 which are drawn in order of the number assigned to each object. More specifically, the object 3401 is disposed at a rearmost side (on a bottom layer) and the object 3419 is disposed at a foremost side (on a top layer). In this state, if a new object 3501 is added, the object 3501 is disposed in front of the object 3419 according to the drawing order assigned to the object 3501.
In FIG. 17, a user may regard the object 3501 as being drawn in front of the object 3412. Therefore, if a user intends to draw the object 3501 between the objects 3411 and 3412, the user generates an instruction “shift rearward” to move the object 3501. However, other objects (i.e., objects 3413 through 3419) are present between the objects 3501 and 3412. Thus, the user is required to repeatedly generate the instruction “shift rearward.”
Furthermore, in a situation illustrated in FIG. 17, even if a user has once generated an instruction “shift rearward”, a target object does not change in appearance although the drawing order of the target object has changed. Thus, a user cannot determine whether the operation was successful.
To solve the problem, a conventional technique discussed in Japanese Patent Application Laid-Open No. 07-152356 specifies an object group overlapping a selected object. Then, an overlapping relationship can be switched in such a manner that the selected object can be switched with an object having a closest overlapping order in the specified object group.
Furthermore, as a method for changing the overlapping order of a plurality of objects, a conventional technique discussed in Japanese Patent Application Laid-Open No. 09-016368 stores a selection order of an object and changes the overlapping of respective objects according to the stored selection order.
However, according to the technique discussed in Japanese Patent Application Laid-Open No. 07-152356, the object being switched with the selected object in overlapping position is an object having been set a closest overlapping order. As a result, if a great number of objects are present between the selected object and the object having been set a desired overlapping order, a user is required to repeatedly execute the overlapping change processing.
Furthermore, according to the technique discussed in Japanese Patent Application Laid-Open No. 09-016368, when a user changes an overlapping relationship, the user is required to select an object according to a desired overlapping order. Therefore, if a great number of objects are present, the user repeatedly executes the selection processing by an amount corresponding to the total number of objects.
Therefore, in any of the above-described conventional techniques, a user cannot easily change the drawing order of a plurality of objects so as to realize a desired overlapping relationship.